EPTsmall brain teaser... enjoy - Page 2
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Tadzio
3340 Posts
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qrs
United States3637 Posts
none are true: I) If 1 is true: 1 -2 and 3 are false 2 -since 3 is false, 4 is true 3 -which means that 2 is true 4 -which contradicts line 1 II) If 2 is true: 1 -3 is true 2 -which means that 4 is false 3 -which means that 2 is false 4 -which contradicts the starting premise III) If 3 is true: 1 -5 is true 2 -which means that 1 is true 3 -which has already been shown to generate a contradiction IV) If 4 is true: 1 -2 is true 2 -which has already been shown to generate a contradiction V) If 5 is true: 1 -1 is true 2 -which has already been shown to generate a contradiction This was following the OP that false means the complete reverse is true, and not simply that the statement is not fully true (but may be true in part). Edit: I realized afterward that I wasn't thorough enough: I checked each statement for trueness, but not for falseness (by the definition used, false is not the same as not-true). However, it's easy to remedy that: + Show Spoiler + 1-4 each say that various other statements are false. If any of 1-4 are false (i.e. its reverse is true), that will make a different statement true. We already showed that none of the statements can be true; therefore none of statements 1-4 can be false. If 5 is false, then 1 & 3 are false, but we just said that 1-4 cannot be false. In short, all 5 statements are neither true nor false. | ||
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Elite]v[arine
United States264 Posts
On August 19 2008 07:08 Leath wrote: Lets see if I understood this correctly + Show Spoiler + statement 1) 2 and 3 are false. statement 2) 1 is false, 3 is true. statement 3) 4 is false, 5 is true. statement 4) 2 is true, 3 is false. statement 5) 1 is true, 3 is true. Starting at 1 = T T 1) 2 false, 3 false F 2) 1 true, 3 false F 3) 4 true, 5 false T 4) 2 false, 3 true go back to 3) T 3) 4 false, 5 true F 4) 2 true, 3 false go back to 2) T 2) 1 false, 3 true go back to 1) F 1) 2 true 3 true T 2) 1 false, 3 true T 3) 4 false, 5 true F 4) 2 true, 3 false Loop??? Or are we just supposed to change the values once? Or are we supposed to find a pattern where all the statements are correct in such a way that the false statements are simply negating the truth? now that you put it like that you made me remmember that my friend was really into computers >_> On August 19 2008 07:13 qrs wrote: Doing it in my head, it seemed to me that + Show Spoiler + none are true: I) If 1 is true: 1 -2 and 3 are false 2 -since 3 is false, 4 is true 3 -which means that 2 is true 4 -which contradicts line 1 II) If 2 is true: 1 -3 is true 2 -which means that 4 is false 3 -which means that 2 is false 4 -which contradicts the starting premise III) If 3 is true: 1 -5 is true 2 -which means that 1 is true 3 -which has already been shown to generate a contradiction IV) If 4 is true: 1 -2 is true 2 -which has already been shown to generate a contradiction V) If 5 is true: 1 -1 is true 2 -which has already been shown to generate a contradiction This was following the OP that false means the complete reverse is true, and not simply that the statement is not fully true (but may be true in part). my brain is having a meltdown.... ill come back and read everything later... | ||
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evanthebouncy!
United States12796 Posts
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fig_newbie
749 Posts
+ Show Spoiler + true false true false true I'm considering there to be three values: false, neutral, true, with all statements starting off as "neutral" with statement 1 and changing it with each new instruction. | ||
Pholon
Netherlands6142 Posts
On August 19 2008 07:04 Doctorasul wrote: Pholon, he specifically said that "each true keeps the statement the same, each false reverses it", so you don't get 3 options. Yeah read that now, in which case I think I'm not finding a solution the way I'm doing it, but Ill give it some more though. | ||
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Makhno
Sweden585 Posts
1:True 2:False 3:True 4:False 5:True It's simple, if you start with 1 and just go down the line this is the answer you get using simple logics. Okay, I gave it some more thougt and in my mind it depends on what you assume 1 to be. If you assume it to be true then my answer is correct, if false then reversed. | ||
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fig_newbie
749 Posts
On August 19 2008 07:30 Makhno wrote: + Show Spoiler + 1:True 2:False 3:True 4:False 5:True It's simple, if you start with 1 and just go down the line this is the answer you get using simple logics. i had the same response but im not so sure now, seeing as statements 1 and 5 contradict each other with regards to 3. | ||
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Pholon
Netherlands6142 Posts
Reason+ Show Spoiler + Consider S3: 1 ) If 3 is true, it says that 5 is true, which says that 1 is true which says that 3 is [i]false (contradiction in italics) 2 ) If [b]3 is false it means that (through full reversal) 4 is true which says that 2 is true which then says that [b]3 is true (contradiction in italics) So you could never find a value for 3, so no solution ...right? | ||
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fig_newbie
749 Posts
its all false. blah, how frustrating | ||
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Pholon
Netherlands6142 Posts
o_O | ||
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Makhno
Sweden585 Posts
On August 19 2008 07:33 fig_newbie wrote: i had the same response but im not so sure now, seeing as statements 1 and 5 contradict each other with regards to 3. Damn, just realized I misread 1... Okay, i'm not seeing a reasonable answer here. | ||
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Piste
6179 Posts
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RaGe
Belgium9947 Posts
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Igakusei
United States610 Posts
2 and 3 cannot be true. If they were true, then three would also be true. Three says that five is true, which says that three is false. Since they can't agree, they are both out. 4 cannot be true because it says that 2 is true. 1 says that 2 and 3 are false, 5 says that 1 is true and 3 is false. Those two are in agreement, and since 2 and 3 are certifiably false, we know that they are true as well. 1,5 True 2-4 False /thread | ||
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Igakusei
United States610 Posts
On August 19 2008 07:49 RaGe wrote: this is really easy for anyone who got a logics course You need to take a course to do elementary logic? | ||
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qrs
United States3637 Posts
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evanthebouncy!
United States12796 Posts
On August 19 2008 07:49 RaGe wrote: this is really easy for anyone who got a logics course Meh posts like this is as good as nothing because it makes it sound like you know wtf is going on yet you offer no insights to it, and sounding off bragging some empty claims. | ||
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Murlox
France1699 Posts
On August 19 2008 08:21 evanthebouncy! wrote: Meh posts like this is as good as nothing because it makes it sound like you know wtf is going on yet you offer no insights to it, and sounding off bragging some empty claims. He obviously barely read it and threw that, to brag On topic : statement 1) 2 and 3 are false. statement 2) 1 is false, 3 is true. statement 3) 4 is false, 5 is true. statement 4) 2 is true, 3 is false. statement 5) 1 is true, 3 is true. Problem... if statement 3 is true, then statement 4 is false, then statement 2 is false, then statement 3 is false. ERROR. ok then, statement 3 must be false. so statement 5 must be false. so statement 1 must be fasle (but then 3 must be true. ERROR) ERROR ERROR ERROR ERROR | ||
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Murlox
France1699 Posts
On August 19 2008 08:14 qrs wrote: edit: decided not to be snarky. Neverborn, your mistake is in assuming that not-true is the same as false here. well... On August 19 2008 06:29 X.xDeMoNiCx.X wrote: ... each true keeps the statement the same, each false reverses it. ... | ||
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